Hidden Triple
Hard
Used by Smart Hint
Same idea as Hidden Pair, but three digits are confined to the same three cells.
- Cells that establish the pattern
- Candidate ruled out
How it works
- Digits 2, 6, and 8 only show up as candidates in A4, A5, and B5 within this box — every other cell has ruled all three out.
- Even though those cells carry a couple of extra candidates (9 and 5), the Hidden Triple lets you strip those extras away, since 2, 6, and 8 must fill exactly those three cells.